Freeze protector

ABSTRACT

The bottom plate of a meter body has a compartment communicating with the main internal cavity of the meter. The compartment also communicates with the exterior through an opening in the bottom plate. This opening is closed off by a plate or plug having a substantially higher heat conductivity than the meter body.

United States Patent [72] Inventor Abraham Branitzky 279 W. 154th St., Harvey, 111. 60426 [2]] Appl. No. 756,231 [22] Filed Aug. 29, 1968 [45] Patented Jan. 5, 1971 [54] FREEZE PROTECTOR 15 Claims, 6 Drawing Figs.

[52] U.S. Cl. 137/60, 73/277 [51] Int. Cl G01f15/10 [50] Field ofSearch 137/59- [56] References Cited UNITED STATES PATENTS 953,199 3/1910 Gamon II 1L 7 Primary Examiner-M. Cary Nelson Assistant Examiner-Richard Gerard Attorney-Milton Robert Kestenbaum ABSTRACT: The bottom plate of a meter body has a compartment communicating with the main internal cavity of the meter. The compartment also communicates with the exterior through an opening in the bottom plate. This opening is closed off by a plate or plug having a substantially higher heat conductivity than the meter body.

freezing. The internal mechanism, the measuring chamber 5, will not be subject to freezing stresses.

Moreover, so long as the water runs, the pipes 16 from the main which run to the meter are also protected from freezing. One need only change the bottom plate at relatively small cost to restore the meter to usefulness.

It is also possible to weaken the threads on the freeze plug 23 so that they will yield and be stripped from the plug at the requisite pressure. In this way the bottom plate 15 can be saved for reuse by removing the stripped threads and inserting a new freeze plug 23.

Referring to FIGS. 4 and 5, a second embodiment is shown in which similar parts bear the same reference numbers as the first embodiment. In this second embodiment; a compartment 25, has a top wall 26 and side walls 27 in the bottom plate 15. A slot 28 passes from the internal cavity 4 through the top wall 26 and communicates with the compartment 25. The compartment is itself a larger slot shape which extends to and opens upon the exterior of the bottom plate 15 Threaded blind holes 29 extend into the bottom plate 15 beyond each end of the compartment 25. Bolts 30 pass through holes 31 in a freeze plate 32 to hold the freeze plate 32 flush against a gasket 33 so as to completely and tightly close off the compartment 25. The freeze plate has a weakening groove 34 located at each end of the compartment 25.

The freeze plate 32 is frangible metal, such as cast iron. The casing, the bottom plate 15 and the bolts 30 are formed of strong plastic. The heat conductivity of the freeze plate 32 is substantially higher than the casing the the bottom plate.

Referring in addition to FIG. 6, the freeze plate functions as follows. As described in connection with the first embodiment, water will fill compartment 25 from cavity 4 through slot 28. When freezing conditions occur the heat of the water in the compartment 25 will be drawn off faster than elsewhere in the meter and the initial freezing will be localized to the water in the compartment 25.

When this water expands in the freezing process, the frangible freeze plate 32 will break at one or both of the weakening grooves 34. The freeze plate will bend away from the compartment or drop away entirely, followed by the ice from the compartment 25 and water from the cavity 4 above it.

lclaim:

1. In a casing having a cavity for receiving a freeze-expanding fluid:

a mechanism within said cavity to be protected from freezing stresses;

means for localizing the initial freezing of said fluid to a predetermined region communicating with said cavity including barrier means for substantially isolating said predetermined region from the portion of said cavity containing said protected mechanism, and adapted to prevent the stresses developed in said initial freezing from being applied upon and within said protected mechanism; and

means responsive to said initial freezing for opening said region to the exterior to said casing.

2. In a casing according to claim 1 wherein said freeze localizing means comprises means for carrying heat away from said predetermined region faster than from said cavity.

3. In a casing according to claim 1 wherein said freeze localizing means comprises at least two materials of dissimilar heat conductivity, the material of higher heat conductivity contacting said predetermined region and the material of lower heat conductivity contacting said cavity.

a 4. In combination with a casing having a cavity for receiving a freeze-expanding fluid and a mechanism within said cavity to be protected from freezing stresses, freeze protection means comprising compartment means communicating with said cavity and capable of being opened to the exterior to said casing, said compartment means being substantially isolated from the portion of said cavity containing said protected mechanism to prevent the freezing stresses developed in said compartment means from being a plied upon and within said protected mechanism, and means or closing off said compartment means from said exterior having a higher heat conductivity than said casing and adapted to open said compartment means to said exterior upon freezing of said fluid in said compartment means.

- 5. The combination according to claim 4 wherein said casing includes a bottom plate which includes said compartment means.

6. The combination according to claim 4 wherein at least a portion of the walls of said compartment means is formed by said closing means.

7. The combination according to claim 4 wherein said casing has an external opening to said compartment means and said closing means comprises plug means secured in said opening and releaseable under the force of said freeze expansion.

8. The combination according to claim 4 wherein said casing has an external opening to said compartment means and said closing means comprises a frangible plate closing off said opening and breakable under the force of said freeze expansion.

9. The combination according to claim 4 wherein said casing is comprised of plastic and said closing means is comprised of metal having a substantially higher heat conductivity than said plastic.

10. The combination according to claim 4 wherein said cavity is closed off by a bottom plate which includes said compartment means and has an external opening to said compartment means and said closing means comprises plug means closing off said opening and releaseable under the force of said freeze expansion.

11. The combination according to claim 4 wherein said cavity is closed off by a bottom plate which includes said compartment means and has an external opening to said compartment means and said closing means comprises a frangible plate closing off said opening and breakable under the force of said freeze expansion.

12. The combination according to claim 4 wherein wall means separate said cavity and said compartment means, said wall means having a relatively small opening between said cavity and said compartment means.

13. ln combination with a casing having a cavity for receiving a freeze-expanding fluid, freeze protection means comprismg:

compartment means communicating with said cavity and capable of being opened to the exterior to said casing; and

means for closing off said compartment means from said exterior having a higher heat conductivity than said casing and adapted to open said compartment means to said exterior upon freezing of said fluid; said casing includes a bottom plate which includes said compartment means.

14. The combination according to claim 13 wherein said bottom plate has an external opening to said compartment means and said closing means comprises a frangible plate closing off said opening and breakable under the force of said freeze expansion.

15. The combination according to claim 13 wherein said bottom plate has an external opening to said compartment means and said closing means comprises plug means closing off said opening and releasable under the force of said freeze expansion. 

1. In a casing having a cavity for receiving a freeze-expanding fluid: a mechanism within said cavity to be protected from freezing stresses; means for localizing the initial freezing of said fluid to a predetermined region communicating with said cavity including barrier means for substantially isolating said predetermined region from the portion of said cavity containing said protected mechanism, and adapted to prevent the stresses developed in said initial freezing from being applied upon and within said protected mechanism; and means responsive to said initial freezing for opening said region to the exterior to said casing.
 2. In a casing according to claim 1 wherein said freeze localizing means comprises means for carrying heat away from said predetermined region faster than from said cavity.
 3. In a casing according to claim 1 wherein said freeze localizing means comprises at least two materials of dissimilar heat conductivity, the material of higher heat conductivity contacting said predetermined region and the material of lower heat conductivity contacting said cavity.
 4. In combination with a casing having a cavity for receiving a freeze-expanding fluid and a mechanism within said cavity to be protected from freezing stresses, freeze protection means comprising compartment means communicating with said cavity and capable of being opened to the exterior to said casing, said compartment means being substantially isolated from the portion of said cavity containing said protected mechanism to prevent the freezing stresses developed in said compartment means from being applied upon and within said protected mechanism, and means for closing off said compartment means from said exterior having a higher heat conductivity than said casing and adapted to open said compartment means to said exterior upon freezing of said fluid in said compartment means.
 5. The combination according to claim 4 wherein said casing includes a bottom plate which includes said compartment means.
 6. The combination according to claim 4 wherein at least a portion of the walls of said compartment means is formed by said closing means.
 7. The combination according to claim 4 wherein said casing has an external opening to said compartment means and said closing means comprises plug means secured in said opening and releaseable under the force of said freeze expansion.
 8. The combination according to claim 4 wherein said casing has an external opening to said compartment means and said closing means comprises a frangible plate closing off said opening and breakable under the force of said freeze expansion.
 9. The combination according to claim 4 wherein said casing is comprised of plastic and said closing means is comprised of metal having a substantially higher heat conductivity than said plastic.
 10. The combination according to claim 4 wherein said cavity is closed off by a bottom plate which includes said compartment means and has an external opening to said compartment means and said closing means comprises plug means closing off said opening and releaseable under the force of said freeze expansion.
 11. The combination according to claim 4 wherein said cavity is closed off by a bottom plate which includes said compartment means and has an external opening to said compartment means and said closing means comprises a frangible plate closing off said opening and breakable under the force of said freeze expansion.
 12. The combination according to claim 4 wherein wall means separate said cavity and said compartment means, said wall means having a relatively small opening between said cavity and said compartment means.
 13. In combination with a casing having a cavity for receiving a freeze-expanding fluid, freeze protection means comprising: compartment means communicating with said cavity and capable of being opened to the exterior to said casing; and means for closing off said compartment means from said exterior having a higher heat conductivity than said casing and adapted to open said compartment means to said exterior upon freezing of said fluid; said casing includes a bottom plate which includes said compartment means.
 14. The combination according to claim 13 wherein said bottom plate has an external opening to said compartment means and said closing means comprises a frangible plate closing off said opening and breakable under the force of said freeze expansion.
 15. The combination according to claim 13 wherein said bottom plate has an external opening to saiD compartment means and said closing means comprises plug means closing off said opening and releasable under the force of said freeze expansion. 